An LED (Light Emitting Diode) is a semiconductor device capable of converting electrical energy to optical energy. An LED driver refers to a power supply adjusting electronic device for driving the LED to emit light or driving an LED module assembly to operate normally. A universal LED driver is generally designed and provided by special companies. These companies modularize it and then provide it to an LED terminal application product manufacturer for use. However, as for some specific applications, such a universal module might not be applicable or cannot work very well. For example, some periods of a vertical synchronous signal provided by the universal LED driver module might have ±5% jitter as compared with a standard signal. In some cases, this jitter amplitude is too large and the signal cannot be directly used.
Therefore, there is a need for re-shaping the vertical synchronous signal for the LED driver so as to reduce or remove jitter thereof.